Background characteristics of a cohort of Swedish hairdressers (All) and a cohort of women from the general population and their children (Referents); background characteristics are also presented for the subgroup of hairdressers (Questionnaire) that answered a questionnaire regarding occupational exposure
| Hairdressers | |||
|---|---|---|---|
| All n (%) | Questionnaire n (%) | Referents n (%) | |
| *Recorded since 1982. | |||
| Infants born | 6960 | 4465 | 6629 |
| Women given birth | 3706 | 2410 | 3462 |
| Calendar year of birth | |||
| 1973–77 | 830 (12) | 486 (11) | 722 (11) |
| 1978–82 | 1122 (16) | 680 (15) | 1041 (16) |
| 1983–88 | 2019 (29) | 1307 (29) | 1866 (28) |
| 1989–94 | 2989 (43) | 1992 (45) | 3000 (45) |
| Maternal age (y) | |||
| 15–19 | 135 (2) | 63 (1) | 238 (4) |
| 20–24 | 2288 (33) | 1415 (32) | 1945 (29) |
| 25–29 | 2957 (42) | 1929 (43) | 2735 (41) |
| 30–34 | 1312 (19) | 888 (20) | 1376 (21) |
| ≥35 | 268 (4) | 170 (4) | 335 (5) |
| Maternal weight (kg)* | |||
| <60 | 572 (16) | 548 (16) | 381 (16) |
| 60–69 | 1166 (33) | 1032 (30) | 732 (31) |
| 70–79 | 1101 (31) | 1039 (31) | 732 (31) |
| ≥80 | 715 (20) | 766 (23) | 492 (21) |
| Unknown | 1701 | 1721 | 1111 |
| Maternal height (cm)* | |||
| <160 | 529 (13) | 348 (13) | 499 (13) |
| 160–164 | 1223 (30) | 787 (29) | 1072 (28) |
| 165–169 | 1236 (30) | 814 (30) | 1189 (31) |
| 170–174 | 901 (22) | 612 (22) | 850 (22) |
| ≥175 | 247 (6) | 167 (6) | 280 (7) |
| Unknown | 1119 | 720 | 1216 |
| Parity | |||
| 1 | 4061 (58) | 2630 (59) | 3696 (56) |
| 2 | 2135 (31) | 1374 (31) | 1993 (30) |
| ≥3 | 764 (11) | 461 (10) | 939 (14) |
| Smoking habits in early pregnancy (cigarettes per day)* | |||
| 0 | 3529 (73) | 2418 (75) | 3508 (75) |
| 1–9 | 876 (18) | 532 (17) | 761 (16) |
| ≥10 | 435 (9) | 256 (8) | 425 (9) |
| Unknown | 415 | 242 | 412 |